Hi, your problem lies with the connector symbols. Whoever made the J? connector symbols, have the pin connections wrong! I hope this image will make it clear! As you can see, there are 2 connectors in the image, 1 labeled H1 and the other J3. J3 is from your schematic, H1 is from EasyEDA EELib pin header part I added to test. H1 has the pins out with the gray point at the end, that is the true connection point. On J3, they are inside, and you have connected them to the line and although it seems to our eyes, that it is connected, the CAD software only sees it connected when the gray points are connected.  Most of the other warnings about incomplete nets are from the Teensy's pins unconnected, ignore the warnings or add the No Connect Flags to feel safe :) K1_3 also could use the N.C. flag.  I hope this helps you! Have fun!

@Raghav Kumar, By all means add [SOLVED] to the title of your topic but please do not delete the whole title and content of your original topic because now, Deskpro's helpful and detailed reply has no context within which anyone else finding this topic can understand it.

@deskpro256 Great answer thanks! That was exactly the problem :)

@andyfierman Sorry, added the question back!